This proposal constitutes the core element in a program of six projects, which in combination address the research task of measuring the major forms of productive behavior, identifying the personal and situational factors that predict such behavior, and exploring its implications for health and well-being. The core project includes the creation and management of a national longitudinal data base, with data collections scheduled in 1984 and 1987, which will provide the analytic materials for the other five projects, each of which will concentrate on a particular set of predictors or consequences of productive activities. The core project also includes the development and validation of measures of the five categories of productive behavior cited in A National Plan for Research on Aging, Report of Subpanel 4, Increasing Productivity Among Older people. These are paid employment; unpaid employment; voluntary organizational activity; mutual help; and self-help. The research design is unusual in combining the attribute of national representatives with other properties that increase its cost-efficiency, versatility, and capacity for causal inference. These properties include the over-sampling (with known probabilities) of blacks and of people 45 years of age or more; and the inclusion of people who were respondents in two national 1979 studies, Supports of the Elderly and National Study of Black Americans (thus extending the longitudinal capacity of the program to three points in time, 1979, 1984, and 1987). The design is further strengthened by the collection of independent data (medical records) for a subsample of respondents, thus making possible comparisons of self-report and medical data (clinical and laboratory).